Background: The 5,10-methylenetetrahydrofolate reductase ( MTHFR ) polymorphisms and low folate levels are associated with inhibition of DNA methyltransferase and consequently DNA hypomethylation. The expanding spectrum of common conditions linked with MTHFR polymorphisms includes certain adverse birth outcome, pregnancy complications, cancers, adult cardiovascular diseases and psychiatric disorders, with several of these associations remaining still controversial. Trisomy 21 or Down syndrome (DS) is the most common genetic cause of mental retardation. It stems predominantly from the failure of chromosome 21 to segregate normally during meiosis. Despite substantial research, the molecular mechanisms underlying non-disjunction leading to trisomy 21 are poorly understood. Materials and Methods: Two common variants C677T and A1298C of the MTHFR gene were screened in 36 parents with DS children and 60 healthy couples from Tamil Nadu and Karnataka. The MTHFR genotypes were studied by RFLP analysis of PCR-amplified products and confirmed by sequencing. Results: The CT genotype was seen in three each (8.3%) of case mothers and fathers. One case father showed TT genotype. All the control individuals exhibited the wild type CC genotype. A similar frequency for the uncommon allele C of the second polymorphism was recorded in case mothers (0.35) and fathers (0.37) in comparison with the control mothers (0.39) and fathers (0.37). Conclusion: This first report on MTHFR C677T and A1298C polymorphisms in trisomy 21 parents from south Indian population revealed that MTHFR 677CT polymorphism was associated with a risk for Down syndrome.

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Pharmacogenetics is the study of genetic basis in the individual response to drugs. A thorough knowledge of this will lead to a future where tailor-made drugs, suiting an individual, can be used. Scandinavian countries have been known for wide usage of pharmacogenetics and the most widely used application is for genotyping CYP2D6 in treating psychiatric illness. The CYP-450 enzyme, a super family of microsomal drug-metabolizing enzymes, is the most important of enzymes that catalyzes phase-I drug metabolism reaction. CYP2D6 is a member of this family and it has been most intensively studied and the best example of pharmacogenetics variation in drug metabolism. Neuro-transmitter and drug acting CNS viz. codeine, dextromethorphan, metoprolol and tryptyline etc. are well metabolized by this enzyme. Thus, CYP2D6 is one of the most important and responsible enzymes which regulates bioavailability and metabolism of drug. Presently 75 alleles of CYP2D6 have been described which are responsible for variance of metabolism and toxicity of drugs. Thus, by determining variance of CYP2D6 using molecular approaches viz., PCR, real-time PCR, DNA micro-array and molecular docking can determine the adverse effects, drug toxicity, bioavailability and therapeutic potential of new drug.

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In this study 250 patients with essential hypertension were investigated in comparison to 218 normotensives for association with epidemiological parameters. Of these DNA samples from 176 patients and 168 controls were analyzed for intron 4 27bp repeat polymorphism of eNOS gene. The study revealed significantly high risk of essential hypertension for individuals who were obese, with a positive family history and with non-vegetarian food habits. Though the intron 4b/a polymorphism of eNOS gene did not reveal any association with essential hypertension in general, males with a/a genotype of the polymorphism did show significantly high risk for developing hypertension.

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We report a rare association of Turner syndrome with both Neurofibromatosis type I and Tuberous Sclerosis. The patient had XO karyotype with Turners stigmata and also had features of Neurofibromatosis 1 in the form of significant cafe-au-lait spots and Plexiform neurofibroma along with typical features of Tuberous Sclerosis complex. Pedigree analysis revealed that the elder brother of the proband in the family also suffered from Tuberous Sclerosis without the manifestation of Neurofibromatosis or any other genetic disorders. We hypothesize that these associations could be due to new independent mutations and also increased maternal and paternal age in a pre-disposition of Turner syndrome.

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Background: Arrythmogenic Right Ventricular Cardiomyopathy (ARVC) is a primary myocardial disorder morphologically characterized by subtle to severe replacement of the right ventricular myocardium by fatty and fibrous tissue. ARVC is known to be highly prevalent in European population with recent reports implicating it to be a major cause of sudden death in young individuals even from American and Asian population. Aim: To implicate or exclude TMEM43 (ARVC-5), DSP(ARVC-8) genes and the yet to be identified gene at ARVC-6 locus in the pathogenesis in three families affected with ARVC from India. Materials and Methods: Three families comprising of 42 affected/unaffected members were included in the study. Three microsatellite markers, D3S3613 (ARVC5) D10S1664 (ARVC6), D6S309 (ARVC8) were genotyped by PCR-based native PAGE. Two-point Linkage analysis was performed using LINKAGE program version 5.2 . Results and Discussion: LOD scores from linkage analysis for the microsatellite marker D10S1664 (ARVC-6) in families KS and REV have shown positive value hinting the involvement of this locus in the etiology of ARVC, while linkage analysis in the SB family ruled out involvement of DSP, TMEM43 and ARVC-6, as negative LOD scores were obtained with all three loci. Therefore, linkage analysis carried out in the present study indicates that ARVC-6 (cumulative LOD score is equal to plus 1.203376 at q is equal to 0.05) could be the locus harboring the mutated gene in two out of three families.

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Kangri cancer is a unique thermally-induced squamous cell carcinoma (SCC) of skin that develops due to persistent use of Kangri (a brazier), used by Kashmiri people, to combat the chilling cold during winter months. We designed a large scale case-control study to characterize the frequency of two polymorphisms within the MHC class III-linked HSP70genes, Hsp70-2 and Hsp70-hom, in order to find any association of these genotypic variants for predisposition to and clinical outcome of Kangri cancer patients from Kashmir valley in North India. Polymerase Chain Reaction and restriction enzymes were utilized to characterize the frequency of two polymorphisms with in Hsp70-2 and Hsp70-hom genes in 118 Kangri carcinoma cases and 95 healthy controls from the same population of Kashmir. Association of high frequency allelic variants of Hsp70genes with various clinico-pathological features of prognostic significance was assessed by Chi-square test using SPSS software. In this study, allelic frequency of Hsp70-2 A/G heterozygote (0.87) ( P = 0.012) was found to be significantly high in Kangri cancer cases compared to control (0.736) with a Relative Risk of 2.45 fold. Conversely, the allelic frequency of Hsp70-2 A/A allele in homozygous condition was significantly low in Kangri cancer cases and worked out to be 0.084 (Vs 0.252 in control) with P is equal to 0.001, implicating it as a protective allele against Kangri cancer in subjects with this genotype . Similarly, significantly high frequency of 0.50 (Vs 0.29 in control) of Hsp70-homC/C allele was found in homozygous condition in Kangri cancer cases suggestive of a positive relative risk associated with this genotype (RR is equal to 2.47) ( P is equal to 0.002) . The overall allele frequency data analysis of Hsp70-2 and Hsp70-hom genes was significant (χ² is equal to 12.38, P is equal to 0.002; and χ² is equal to 12.21, P is equal to 0.002). The study also reveals considerable association of high frequency alleles of HSP70genes, especially of Hsp70-2 A/G or G/G in Kangri tumors with clinico-pathological features of poor prognosis. These results indicate that the relative risk of Kangri cancer associated with Hsp70-2 and Hsp70-hom gene polymorphisms is confined to Hsp70-2 A/G or G/G and Hsp70homC/C haplotype in our population. The study, therefore, suggests Hsp70-2 A/G or G/G and Hsp70homC/C genotypes as potential susceptibility markers and independent prognostic indicators in Kangri carcinoma patients in Kashmiri population.

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We describe a combination case of Down's syndrome and Cardiac Tamponade with Pulmonary Tuberculosis in an adult patient.

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